000
FXUS62 KGSP 012329
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
729 PM EDT SAT AUG 1 2015
.SYNOPSIS...
DRY HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE AREA THROUGH THE
WEEKEND. LOW LEVEL MOISTURE WILL GRADUALLY RETURN NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 730 PM EDT SATURDAY...CURRENT FCST REMAINS ON TRACK THEREFORE
ASIDE FOR MINOR TWEAKS TO TEMPERATURES/DEWPOINTS AND SKY TO ACCOUNT
FOR MOST RECENT OBS/SAT...NO SIG CHANGES WERE NEEDED/MADE WITH THIS
UPDATE. OVERNIGHT LOWS FALLING INTO THE 50S ACROSS THE HIGHER
TERRAIN AND MID/UPPER 60S OVER THE LOWER TERRAIN SHOULD ALLOW FOR A
VERY NICE EARLY AUGUST EVENING ACROSS THE REGION.
PREVIOUS DISCUSSION...
AS OF 215 PM...NOT MUCH CHANGE IN THE UPPER PATTERN THRU THE NEAR
TERM...WITH A PERSISTENT TROF OVER THE EASTERN CONUS AND LARGE RIDGE
ACRS THE WEST. AN UNUSUALLY DRY AIR MASS FOR THIS TIME OF YEAR HAS
SETTLED IN ACRS THE AREA. THIS SHUD KEEP POPS AT A MINIMUM WITH JUST
A FEW CLOUDS HERE AND THERE. TEMPS WILL NEAR OR EVEN A DEG OR TWO
BELOW NORMAL IN SPOTS TONIGHT.
SUNDAY...MODELS HINT AT SOME RETURN OF LLVL MOISTURE INTO THE
AREA...AS SFC HIGH PRES BUILDS INTO THE CENTRAL
APPALACHIANS...ALLOWING FOR A LIGHT EASTERLY FLOW ATOP THE CWFA. THE
NAM IS MOST BULLISH ON THIS...AND HAS SOME CONVECTIVE RESPONSE IN
THE NC MTNS. THIS AND THE SREF ARE ABOUT THE ONLY MODELS THAT SHOW
THIS. I WILL KEEP A SLGT CHC POP FOR THE TYPICAL CENTRAL AND SW NC
MTN PEAKS THAT OFTEN STILL TRIGGER CONVECTION IN SPITE OF DRY
GUIDANCE. TEMPS WILL RISE TO A CATEGORY OR TWO ABOVE NORMAL AGAIN
WITH MOSTLY SUNNY SKIES EXPECTED.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
AS OF 215 PM SATURDAY...IT LOOKS LIKE OUR QUIET WEATHER WILL REMAIN
AT LEAST INTO MONDAY...THEREAFTER WE CAN EXPECT A RETURN TO MORE
DIURNAL THUNDERSTORM CHANCES AS LOW LEVEL MOISTURE STARTS TO
IMPROVE. THE DRY WEATHER CONTINUES ON SUNDAY NIGHT AND MONDAY AS WE
SHOULD STILL BE AT THE BOTTOM OF AN UPPER TROF WITH A WNW FLOW
ALOFT. DEWPOINT WILL PROBABLY MIX OUT AGAIN ON MONDAY AFTERNOON...
DOWN INTO THE 50S IN MANY PLACES E OF THE MTNS...WHICH WOULD CUT
BACK ON THE POTENTIAL FOR POSITIVE BUOYANCY. THE NAM ACTUALLY
DEVELOPS A MOISTURE BOUNDARY NEAR THE EASTERN FRINGE OF FCST AREA...
WHICH THE MODEL ACTS UPON WITH SHOWER DEVELOPMENT. FOR NOW...THIS
WAS DISCOUNTED AS BEING AN OUTLIER. THE FCST WAS KEPT DRY OVER THE
PIEDMONT...THRU TUESDAY MORNING. SOME CHANGES WILL BEGIN ON TUESDAY
AS A SHORT WAVE TO THE WEST BEGINS TO FLATTEN AND LIFT THE TROF.
THIS ALLOWS MOISTURE TO INCREASE AS A SURFACE BOUNDARY STARTS TO SAG
DOWN INTO THE REGION FROM THE N. THE INCREASED BUOYANCY COMBINED
WITH THE POTENTIAL TRIGGER SUGGESTS A BETTER CHC FOR AFTERNOON
STORMS...AT LEAST OVER THE NC PART OF THE FCST AREA...SO PRECIP
CHANCES WERE NUDGED A BIT ABOVE GUIDANCE. TEMPS WILL CLIMB A BIT
EACH DAY...BUT RH WILL BE LOW ENOUGH SO AS TO KEEP HEAT INDEX BELOW
ADVISORY CRITERIA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 215 PM SATURDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
WEDNESDAY WITH BROAD UPPER TROFFING CENTERED OVER THE GREAT LAKES AND
PERSISTENT UPPER RIDGING OVER THE WESTERN CONUS. OVER THE NEXT COUPLE
OF DAYS...THE PATTERN IS EXPECTED TO DEAMPLIFY TO SOME DEGREE AS THE
UPPER TROF LIFTS TO THE NE AND ANOTHER NORTHERN STREAM UPPER TROF HELPS
TO FLATTEN THE RIDGE OVER THE WEST. AT THE SAME TIME...A SERIES OF FAIRLY
POTENT LOOKING EMBEDDED UPPER SHORTWAVES APPROACH THE FCST AREA FROM
THE WEST AND NW. AT THE SFC...THE SUBTROPICAL BERMUDA HIGH WILL MAINTAIN
ITS INFLUENCE OVER THE SE REGION THRU MOST OF THE PERIOD WITH GENERALLY
LIGHT SLY FLOW. AS HAS BEEN THE CASE OVER THE PAST COUPLE OF WEEKS...THE
LONG RANGE MODELS DO NOT APPEAR VERY CONSISTENT WITH THE EVOLUTION OF
THE SFC PATTERN FOR MOST OF THE MEDIUM RANGE. THEY ATTEMPT TO SPIN UP
SOME SORT OF LOW ON THRUS AND MOVE IT OFFSHORE BY FRI AND THEN DEVELOP
ANOTHER LOW JUST TO OUR WEST ON FRI AND END WITH DRIER CONDITIONS
FOR SAT. AT THIS POINT...IT IS DIFFICULT TO PLACE MUCH CONFIDENCE ON
ANY SPECIFIC MODEL SOLUTION SO I OPTED FOR AN OVERALL BLEND. POPS INCREASE
FOR THURS AND FRI AND TAPER BACK AGAIN ON SAT BUT STILL REMAIN AT SLIGHT
TO SOLID CHANCE. TEMPS START OUT ABOVE NORMAL AND THEN COOL A FEW DEGREES
TOWARDS THE END OF THE WEEK.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...VFR. MOSTLY CLEAR SKIES WILL PREVAIL
THROUGH THE EVENING AS HIGH PRESSURE CONTINUES TO DOMINATE. THAT
SAID...NAM RH/SOUNDINGS DO INDICATE POSSIBLE 080-090 FEW STRATUS
ALONG THE I85 CORRIDOR BY EARLY/MID MORNING...THUS ALL ADJACENT
SITES HAVE SUCH HOWEVER SHOULDNT BE OF ANY IMPACT. OTHER THAN BRIEF
CHANNELED GUSTING AT KAVL...LIGHT NORTHERLY WINDS AT ALL SITES WILL
REMAIN LIGHT/CALM OVERNIGHT ALL THE WHILE SLOWLY VEERING EAST BY
MID/LATE MORNING SUNDAY AT AROUND 6-10KTS. STILL SEEING SOME
MOISTURE TRAPPED BENEATH MID LEVEL INVERSION ON SUNDAY THEREFORE ALL
TAFS ONCE AGAIN CARRY LOW VFR FEW/SCT CU.
OUTLOOK...FLIGHT CONDITIONS WILL REMAIN RESTRICTION FREE THROUGH THE
WEEKEND AHEAD OF GRADUALLY INCREASING PRECIPITATION/RESTRICTION
CHANCES THROUGH MID WEEK AS MOIST SOUTHERLY FLOW RETURNS.
CONFIDENCE TABLE...
23-05Z 05-11Z 11-17Z 17-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK/CDG
SHORT TERM...PM
LONG TERM...JPT
AVIATION...CDG